style.css

html, body {
    height: 100%;
    margin: 0;
    display: flex;
    flex-grow: 1;
    justify-content: center;
    align-items: center;
    font: 1em "Fira Sans", sans-serif;
}
input, #result {
    width: 420px;
    max-width: 90vw;
    font-size: 1em;
    padding: 8px 10px 8px 10px;
    border: 1px solid #cecece;
    background: #fcfcfc;
    border-radius: 4px;
    box-sizing: border-box;
    margin: 12px;
}
input:focus {
    outline: none;
    border: 2px solid #cecece;
    margin: 11px;
}

.column {
    flex-grow: 1;
    display: flex;
    justify-content: center;
    align-items: center;

    max-width: 1280px;
    position: relative;
    height: 100%;
}

#readme a {
    padding: 0.5em;
    position: absolute;
    bottom: 0;
    right: 0;
    text-decoration: none;
    color: #1c1c1c;
}
#readme a:visited {
    color: #4a4a4a;
}

#result {
    overflow: auto;
}
#result::-webkit-scrollbar {
    display: none;
}

:root {
    --green: green;
    --yellow: yellowgreen;
    --orange: orange;
    --red: red;
}
#result.strict-match {
    border-color: var(--green);
    box-shadow: 0 0 4px var(--green);;
}
#result.partial-match {
    border-color:  var(--yellow);
    box-shadow: 0 0 4px var(--yellow);
}
#result.other-pattern-match {
    border-color: var(--orange);
    box-shadow: 0 0 4px var(--orange);
}
#result.no-match {
    border-color: var(--red);
    box-shadow: 0 0 2px var(--red);
}
#result.empty {
    opacity: 35%;
    user-select: none;
}